All Questions
5
questions
2
votes
1
answer
138
views
How does violation of normality conditions affect p-values (relative to permutation tests)
I am running some t-tests using data from small samples (n=25) whose distributions do not appear to be normally distributed (they are not extremely skewed, but the skew is apparent in the plots and ...
3
votes
3
answers
1k
views
Papers About Permutation Version of Welch's t-test
Permutation tests seem to provide a promising alternative for the unpaired t-test, requiring fewer assumptions. However, the core assumption of the permutation test, exchangeability, implies ...
3
votes
0
answers
113
views
When can I use a permutation test to see if means of two distributions differ without Type I errors?
I am analyzing psych experiments which generally take the form of a list of outcome measures for the test and control groups, with roughly equal sample sizes, and I would like to compare their means ...
- 193
6
votes
2
answers
370
views
What is an example of data where the permutation test succeeds but a normal t-test fails?
In literature, I normally see authors use a two sample permutation test on normal data to show that it works as well as the two sample t-test. However, the real power for permutation tests should be ...
- 2,107
63
votes
7
answers
54k
views
Which permutation test implementation in R to use instead of t-tests (paired and non-paired)?
I have data from an experiment that I analyzed using t-tests. The dependent variable is interval scaled and the data are either unpaired (i.e., 2 groups) or paired (i.e., within-subjects).
E.g. (...
- 14.3k